A Use After Free vulnerability in the Routing Protocol Daemon (rdp) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated network-based attacker to cause Denial of Service (DoS). When a BGP session flap happens, a Use After Free of a memory location that was assigned to another object can occur, which will lead to an rpd crash. This is a race condition that is outside of the attacker's control and cannot be deterministically exploited. Continued flapping of BGP sessions can create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS: All versions prior to 18.4R2-S9, 18.4R3-S11; 19.1 versions prior to 19.1R3-S8; 19.2 version 19.2R1 and later versions; 19.3 versions prior to 19.3R3-S5; 19.4 versions prior to 19.4R2-S6, 19.4R3-S6; 20.1 version 20.1R1 and later versions; 20.2 versions prior to 20.2R3-S3; 20.3 versions prior to 20.3R3-S2; 20.4 versions prior to 20.4R3-S1; 21.1 versions prior to 21.1R3-S3; 21.2 versions prior to 21.2R2-S1, 21.2R3. Juniper Networks Junos OS Evolved All versions prior to 20.4R3-S4-EVO; 21.1-EVO versions prior to 21.1R3-S2-EVO; 21.2-EVO versions prior to 21.2R3-EVO; 21.3-EVO versions prior to 21.3R2-EVO.
Solution:
Workaround:
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
| Link | Tags |
|---|---|
| https://kb.juniper.net/JSA69879 | vendor advisory |